Any time new technology makes its way onto the PGA Tour, it’s always interesting to take a step back and observe some of the general trends to see what we can learn from the new data it provides. One new piece of technology that is growing in popularity on professional tours is BodiTrak, which I co-developed. BodiTrak a pressure-sensing mat that helps athletes understand how they interact with the ground, which, of course, is great for the golf swing. As we continue to learn, the movement of a golfer’s center of pressure, or COP, is crucial to performance, and that’s exactly what BodiTrak measures.

The importance of pressure or weight shift isn’t a new concept at all, though. Hall of Fame instructor Jim McLean wrote an article for Golf Digest 25 years ago that discussed the importance of being able to load into your trail leg and explode onto your lead leg. McLean’s postulate from 1980 was resisted by some, but is now being confirmed — almost universally across the instruction community — with data from BodiTrak mats.

“Now with BodiTrak Pressure Mapping, even those most pessimistic doubters and anti-weight movement teachers have to concede that great ball strikers and all PGA Tour players load pressure into the trail foot in the backswing for a driver,” McLean says. “They then unload quickly back to the lead foot, and explode out of the ground through the impact interval.”

We’re only scratching the surface in terms of data collection on Tour, but I wanted to share a few of the most notable trends, as they might be relevant lessons for the average club golfer.

Tour players load and explode

The vast majority of Tour players load at least 80 percent of the pressure into their trail leg in their backswing and at least 80 percent into their lead leg at impact with their driver swing. Some golfers that BodiTrak has measured, like Jason Day, put as much as 95 percent of their pressure on their trail leg near the top of their backswing.

We know that Jason Day uses the ground to generate power, but now we see HOW with the trace from his BodiTrak mat. pic.twitter.com/Ik4bHHkjHI

— BodiTrak Sports (@boditraksports) August 25, 2015

This move requires tremendous physical ability, but it’s foundational to Tour-level distance and consistency. Titleist Performance Institute co-founder Dave Phillips analyzed how Day’s elite hip mobility and stability make this move possible. Many amateurs (and some professionals) don’t have the requisite physical capabilities to do this, while others have inefficient technique. McLean refers to the transition to the lead leg as the key move in the golf. Golfers who fail to do so invite a number of potentially harmful swing tendencies. As PGA Tour instructor John Tillery says, “I’m convinced that the overwhelming difference between amateurs and Tour players is how and when they shift their pressure.”

Most Tour players have a linear trace with short irons

As a general rule, we’ve found the golf club wants to follow a golfer’s pressure trace during the swing. Many instructors advocate a linear trace because it encourages a neutral club path from which golfers can either fade or draw the ball. There are exceptions, but if you review BodiTrak’s library of PGA Tour data, you’ll see that linear traces are extremely common in precision swings. Linear iron traces are often drastically different from dynamic traces seen in many powerful driver swings. The explosive speed of a Bubba Watson or J.B. Holmes results from tremendous ground reaction forces, evidenced by a center of pressure trace we often refer to as a “Z Trace.”

A look at the footwork of long hitters J.B. Holmes and Bubba Watson. #PGATOUR pic.twitter.com/tc1f71fqhr — PGA TOUR (@PGATOUR) March 8, 2015

You may know PGA Tour instructor Scott Hamilton from the instruction videos he makes for GolfWRX. He does an excellent job of explaining the relationship between club path and ground mechanics in the video below.

Sometimes poor technique is to blame for a center of pressure that traces excessively to the ball of the lead foot, but it’s also often an indication of limited physical capacity, specifically in the posterior chain. PGA Tour instructor Mark Blackburn notes that this is especially common among junior golfers who lack stability in their lower body.

“Golfers who lack stability might see CoP trace excessively to toes of lead foot. Common among Jrs.” @BlackburnGolf pic.twitter.com/hD6wmQSa0D

— BodiTrak Sports (@boditraksports) October 29, 2015

Ground interaction is important in the short game

One of the most fascinating studies of ground mechanics has come from how PGA Tour players shift their pressure around the green. PGA Tour instructor Jake Thurm uses BodiTrak to assess how two-time champion Kevin Steelman distributes his pressure to ensure that the loft of the club is maximized. It’s a really interesting look into how data from BodiTrak can reflect corrections in posture throughout a swing. As Thurm says, “If your pressure is incorrect at setup, it will be corrected for throughout your motion.”

Popular online instructor Mark Crossfield, who also contributes to GolfWRX, compared pressure shift trends on different pitch shots, demonstrating how his center of pressure went into the toe of his trail foot and heel of his lead foot on a lob shot versus a lower, spinning chip that was hit with a more linear trace and more pressure into the lead foot at impact.

European Tour member Oliver Wilson also noted the importance in the timing and magnitude of his pressure shift in the bunker.

Following on from yesterday I used @boditrak in the bunker to show how my COP (Center of pressure) was working. It shows the COP moving to the right too soon & then into my heel. Ideally I need to stay more centered with the pressure in the initial takeaway. This will allow me to coil better & enable the right arm to bend easier. These in turn help me to keep the loft on the club face. For me, that will take care of any shaft lean at impact therefore using the bounce! Very similar to my golf swing! Love @boditrak as a measuring device for when things are good but it’s great to sometimes show why we aren’t able to obtain certain positions on video. #bunker #instagolf #golf #Callaway #oriongroup #hugoboss #practice #bounce A video posted by Oliver Wilson (@oliver_wilson) on Mar 30, 2016 at 12:00pm PDT

Pressure shift isn’t a new concept in golf. Instructors have been teaching pressure shift for years, but now, thanks to technologies like BodiTrak, we’re able to validate the concept with data and provide valuable biofeedback on the range for golfers.